/*
 * MIT License
 *
 * Copyright (c) 2023 北京凯特伟业科技有限公司
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
package com.je.bpm.common.el;

import de.odysseus.el.ExpressionFactoryImpl;

import javax.el.ELContext;
import javax.el.ExpressionFactory;
import javax.el.ValueExpression;
import java.util.Map;

import static com.je.bpm.common.el.CommonELResolversUtil.*;

/**
 * 基于JUEL的表达式解析器
 */
public class JuelExpressionResolver implements ExpressionResolver {

    private final ExpressionFactory expressionFactory;

    public JuelExpressionResolver() {
        this(new ExpressionFactoryImpl());
    }

    public JuelExpressionResolver(ExpressionFactory expressionFactory) {
        this.expressionFactory = expressionFactory;
    }

    @Override
    public <T> T resolveExpression(String expression, Map<String, Object> variables, Class<T> type) {
        if (expression == null) {
            return null;
        }
        final ELContext context = buildContext(variables);
        final ValueExpression valueExpression = expressionFactory.createValueExpression(context, expression, type);
        return (T) valueExpression.getValue(context);
    }

    protected ELContext buildContext(Map<String, Object> variables) {
        return new ELContextBuilder()
                .withResolvers(
                        arrayResolver(),
                        listResolver(),
                        mapResolver(),
                        jsonNodeResolver(),
                        beanResolver()
                )
                .withVariables(variables)
                .build();
    }
}
